Apparatus and method for extruding stripes onto an extruded product

ABSTRACT

An apparatus for extruding a jacket and/or insulative material onto an extruded product with one or more longitudinal stripes incorporated onto the surface of said extruded product comprising a body, a primary feed conduit for conveying a primary extrusion material, a striping die, a secondary feed conduit for conveying a secondary extrusion material, a striping die adapter, a striping feed conduit extending through the striping die adapter for conveying striping extrusion material. The striping die adapter may also include a thermocouple for maintaining the viscosity of the striping extrusion material and a thermocouple for monitoring the temperature of said striping die adapter. The striping die includes one or more striping extrusion outlets for conveying striping extrusion material onto the extruded product. The striping die may also include a wishbone-shaped trough for delivering equal amounts of striping extrusion material to said extrusion outlets for extrusion onto the product.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENTS REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO A COMPACT DISK APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an apparatus and method for producing extrudedproducts, and particularly to incorporating longitudinal stripes ontoextruded products useful in color coding the extruded products foridentification, decorative, and other useful purposes.

2. Description of the Related Art

While this invention relates generally to extruded products, forpurposes of illustration, references will be made to electricallyinsulating coatings for cable or wire. However, the invention isapplicable to other products such as extruded pipe and other extrudedproducts.

The outer jacket or insulative material of an electric wire or cable isformed by means of extrusion coating. It is well-known that manyelectrical conducting wires are jacketed and/or insulated withthermoplastic materials such as polyethylene, polyvinyl chloride, ornylon. Such materials may be applied to the surface of a wire bywell-known extruding apparatus and methods using an extrusion apparatusdesigned for this purpose.

Methods and apparatus for producing striped cable are also known in theart. Stripes are often incorporated onto extruded products in order toidentify such extruded products. For example, a wire or a cable may berun from one end of a building to another end and different colorstripes help to identify the wires at the opposite end and preventerroneous connections from being made.

Various methods of striping extruded products have been used in thepast. For example, an ink striping method applies a stripe of coloredink to wire by means of a wheel running in an ink bath and transferringthe ink to the surface of the wire coating, or alternatively, uses aneedle running along the surface of the wire through which ink is forcedthrough the needle and onto the coating. Another method of stripinginvolves utilizing multiple extruders containing different coloredmaterials to form a multi-colored or striped coating on the wire. Inthis method, the separate stripe extruder is often provided for thepurpose of extruding one or more stripes on the surface of the jacket orinsulating material of the conductor.

The current invention provides many advantages over the prior art. Thecurrent invention involves combining the step of extruding stripes ontoan extruded product with the step of extruding a jacket and/orinsulative materials onto the extruded product. The combination of thesetwo steps eliminates time loss and costly logistics involved inextruding the stripes and the jacket and/or insulative material onto theextruded product in two separate steps. Additionally, the stripingextrusion assembly of the current invention is adaptable to an existingextrusion apparatus and can be easily removed and placed onto anotherexisting extrusion apparatus. The portable and exchangeable nature ofthe striping extrusion assembly provides for versatility andadaptability of the extrusion apparatus.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a method and apparatus for the extrusionof stripes onto extruded products useful in color coding said extrudedproducts for identification, decorative, or other useful purposes.

According to one embodiment of the present invention, an extrusionapparatus provides for the extrusion of a primary extrusion materialonto an extruded product, the extrusion of a secondary extrusionmaterial onto an extruded product, and the extrusion of one or morestripes onto the extruded product using a striping die with one or moreextrusion chambers therein. The extrusion device may also include astriping die adapter to connect the striping die to the stripingextruder for transfer of extrusion material onto the striping die forextrusion onto the extruded product. The striping die adapter may alsoinclude a heating element for maintaining the viscosity of the stripingextrusion material. The striping die adapter may also include athermocouple port adapted to a thermostat for monitoring and controllingthe temperature of said striping die adapter.

In another embodiment, an apparatus is used for extruding one or morestripes onto the extruded product. The apparatus comprises a stripingdie with an upstream and downstream side wherein the upstream side ofstriping die is removably connectable to an apparatus for extruding anouter jacket and/or insulative material onto the extruded product. Theapparatus further comprises a striping die adapter with an upstream anddownstream side, the upstream side being removably connectable to saiddownstream side of the striping die. The apparatus may further include aheating element removably connectable to the striping die adapter and athermocouple port connected to the striping die adapter.

In another embodiment, the extrusion of the extruded product with one ormore longitudinal stripes thereon is accomplished by providing astriping die with an upstream and downstream side wherein the upstreamside of the striping die is removably connectable to an apparatus forextruding an outer jacket and/or insulative material onto the extrudedproduct. The method further comprises providing a striping die adapterwith an upstream and downstream side, the upstream side being removablyconnectable to the downstream side of the striping die. The method mayfurther include providing a heating element removably connectable to thestriping die adapter and a thermocouple port connected to the stripingdie adapter.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

A more complete appreciation of the present invention is provided byreference to the following detailed description of the appended drawingsand figures. The following description in conjunction with the appendedfigures enables a person having skill in the art to recognize thenumerous advantages and features of the present invention byunderstanding the various disclosed embodiments. It should beunderstood, however, the invention is not limited to the precisearrangements in the instrumentality shown. The following figures areutilized to best illustrate these features:

FIG. 1 illustrates an overview of an improved extrusion device;

FIG. 2 provides a cross section view of an apparatus for extruding anouter jacket and/or insulative material and one or more longitudinalstripes onto an extruded product according to one aspect of theinvention;

FIG. 3 illustrates a side elevation view of a striping extrusionassembly according to one aspect of the invention;

FIG. 4 illustrates a front elevation view of a striping die adapteraccording to one aspect of the invention;

FIG. 5 illustrates a back elevation view of a striping die adapteraccording to one aspect of the invention;

FIG. 6 illustrates a front elevation view of a single striping dieaccording to one aspect of the invention;

FIG. 7 illustrates a back elevation view of a single striping dieaccording to one aspect of the invention;

FIG. 8 illustrates a front elevation view of a dual striping dieaccording to one aspect of the invention; and

FIG. 9 illustrates a back elevation view of a dual striping dieaccording to one aspect of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The following discussion is presented to enable a person skilled in theart to make and use the present invention. The general principlesdescribed herein may be applied to embodiments and applications otherthan those specifically detailed below without departing from the spiritand scope of the present invention. Therefore, the present invention isnot intended to be limited to the embodiments expressly shown, but is tobe accorded the widest possible scope of invention consistent with theprinciples and features disclosed herein.

Referring to FIG. 1, an extrusion device 12 of the present invention isshown. Extrusion device 12 comprises, from upstream to downstream, apayout station 5 (which may comprise multiple payout reels 38), anextrusion station 1, a primary extruder 3, a secondary extruder 4, astriping extruder 2, and a takeup station 6. The payout station 5 maycomprise a plurality of payout reels 38 about which is wound a bareconductor or wire 9, e.g., copper wire. From the payout station 5, thebare wire 9 travels to the extrusion station 1, where individualextruders 2, 3, and 4 supply a material such as, but not limited to, ajacket and/or insulating material for coating the extruded product. Thematerial is extruded onto the bare wire 9 passing through the extrusionstation 1. The material may be of any suitable jacket or insulatingmaterial such as PVC, nylon, or polyethylene. After the bare wire 9 orextruded product 10 is coated with one or more coats of jacket orinsulating material, it enters a cooling trough 43 containing watervarying in temperature from its upstream end to its downstream end. Thetemperature of the water in the cooling trough 43 may decrease fromupstream to downstream in order to sufficiently cool the extrudedproduct 10.

Referring to FIG. 2, the extrusion station 1 of the extrusion device 12is shown. Bare wire 9 is fed into the extrusion station 1 from thepayout station 5 (see FIG. 1). A primary feed conduit 32 allows forfeeding of a primary extrusion material into a primary extrusion chamber34 for extrusion onto the bare wire 9 or extruded product 10. Asecondary feed conduit 33 is provided for feeding a secondary extrusionmaterial into a secondary extrusion chamber 40 for extrusion onto thebare wire 9 or extruded product 10. The primary extrusion materialtravels through the primary feed conduit 32 from a primary extruder 3and into the primary extrusion chamber 34 defined by a primary extrusionhead 35, a body 37 and a secondary extrusion head 36. The primaryextrusion head 35 may be spiral as shown or any configuration known inthe art. As the primary extrusion material emerges from the primaryextrusion chamber 34 just downstream of the secondary extrusion chamber40, it coats the bare wire 9 or extruded product 10 in a uniform mannerresulting in an extruded product 10 with a protective jacket orinsulative coating around it.

The secondary extrusion material may be either the same material as theprimary extrusion material with the exception that it may be pigmenteddifferently to exhibit a different color or it can be selected frommaterials that are at least compatible with the primary extrusionmaterial. The secondary extrusion material enters the secondaryextrusion chamber 40 via the secondary feed conduit 33. The secondaryextrusion material contacts and penetrates the stream of the primaryextrusion material where the primary extrusion chamber 34 meets themandrel 39, resulting in the formation of a dual coated extruded product10 which then passes through a striping die 7 where striping extrusionmaterial contacts and penetrates the secondary extrusion materialresulting in the formation of one or more longitudinal stripes ofextrusion material on and within the exterior surface of the secondaryextrusion material. As the wire 9 passes through the die adapter 8, theend product is formed comprising an extruded product 10 with a jacketand/or insulative coat which includes one or more longitudinalidentifying stripes on its outer surface.

Primary extrusion head 35 and secondary extrusion head 36 together withthe mandrel 39 and striping die 7 function to direct the flow of fluentextrusion material onto the bare wire 9 to form an extruded wire orproduct 10 with one or more stripes thereon.

The striping die 7 is removably connectable to an existing extrusionstation 1 within a die retainer 41 as more fully disclosed below. Thedie cap 42 functions to secure the die 7 into the die retainer 41. Thestriping die adapter 8 is removably connectable to the striping die 7 asshown in FIG. 3 and more fully described below.

With reference to FIG. 3, a striping extrusion assembly 15 is shown. Theassembly includes the striping die 7, removably attached to the stripingdie adapter 8, which is threadedly attached to an extruder nipple 14,which is removably attached to the striping extruder 2. The striping die7, die adapter 8, and nipple 14 may be manufactured using any suitablematerial such as stainless tool steel. Extrusion material used forextruding one or more stripes on the surface of the extruded product 10flows through the striping extruder 2 in the direction of the arrowshown 16. The extrusion material travels through the striping extruder2, to the extrusion nipple 14, into the striping die adapter 8, which isheated by a heating element 13 to maintain the viscosity of the stripingmaterial. The striping extrusion material then travels through thestriping die 7 (discussed in detail below) onto the extruded product 10or wire 9. The heating element 13 may be any suitable heating elementknown to one of skill in the art, but will preferably be made from aflexible material so as to be easily adaptable to the striping dieadapter 8. The temperature of the striping die adapter 8 may bemonitored and regulated via a thermocouple and thermostat (not shown).The striping die adapter 8 may be equipped with a thermocouple port 17in which a thermocouple may be removably inserted in order to measureand regulate the temperature of the striping die adapter 8.

FIG. 4 shows the front side of the striping die adapter 8, the frontside being removably connectable to the striping die 7. The threadedconnection 18 of the striping die adapter 8 is used to threadablyconnect the extruder nipple 14 to the striping die adapter 8. Theextruder nipple 14 is then removably connected to the striping extruder2. The mounting holes 19 may be used to removably connect the stripingdie adapter 8 and the striping die 7 and to removably connect thestriping die 7 to the remainder of the extrusion station 1 as shown inFIG. 2. The demounting holes 20 may be used to separate the striping dieadapter 8 from the striping die 7 in the event the two cannot beseparated without the use of tools.

FIG. 5 is a depiction of the backside of the striping die adapter 8.Dowel pins 21 are used to removably connect the striping die adapter 8to the front of the striping die 7 (see FIG. 6). The mounting holes 19again are used to removably connect the striping die adapter 8 to thestriping die 7 and to removably connect the striping die 7 to theremainder of the extrusion station 1 as shown in FIG. 2. The demountingholes 20 are used to separate the striping die adapter 8 from thestriping die 7 in the event the two cannot be disconnected without theuse of tools. The flow of the striping extrusion material flows from thestriping extruder 2, to the extruder nipple 14, through the threadedconnection 18 in the striping die adapter 8, through an internal chamber(not shown) of the striping die adapter 8 and out the backside of thestriping die adapter 8 through the extrusion outlet hole 22 and onto thestriping die 7, as more fully discussed below.

One embodiment of the invention may include a single striping die 7′that extrudes one stripe onto the extruded product 10 or wire 9, andanother embodiment of the invention may include extruding two or morestripes onto the extruded product 10 or wire 9. FIGS. 6 and 7 depict thesingle striping die 7′ for extruding a single stripe onto wire 9 or anextruded product 10. FIGS. 8 and 9 depict a double striping die 7″ forextruding two or more stripes onto an extruded product 10.

The front side of the single striping die 7′ in FIG. 6 is removablyattachable to the backside of the striping die adapter 8 shown in FIG.5. Specifically, the dowel pins 21 of the striping die adapter 8 of FIG.5 are removably insertable into the dowel pin holes 23 on the front ofthe single striping die 7′ shown in FIG. 6. The mounting holes 24 on thefront of the single striping die 7′ are used to removably attach thesingle striping die 7′ to the striping die adapter 8 and to theremainder of the extrusion station 1 as shown in FIG. 2. The extrusionoutlet hole 22 on the back of the striping die adapter 8 is in flowcommunication with the extrusion chamber 25 on the front of the singlestriping die 7′. The striping extrusion material then flows through theextrusion chamber 25 of the single striping die 7′ to the outlet 26 onthe back of the single striping die 7′ shown in FIG. 7 and onto theextruded product 10 or wire 9.

In another embodiment shown in FIGS. 8 and 9, the double striping die 7″provides for the extrusion of two or more stripes onto the extrudedproduct 10 or wire 9. The front side of the double striping die 7″provides two holes 27 for inserting the dowel pins 21 on the back sideof the striping die adapter 8. The mounting holes 28 are used toremovably attach the double striping die 7″ to the striping die adapter8 and to the remainder of the extrusion station 1 as shown in FIG. 2.The wishbone-shaped flow channel 29 on the front of the dual stripingdie 7″ is in flow communication with the outlet 22 of the striping dieadapter 8. The extrusion product flows from the striping die adapter 8through the outlet 22 onto the wishbone-shaped flow channel 29 on thefront of the double striping die 7″ and down through the wishbone-shapedflow channel 29 to the extrusion chambers 30 and out of the extrusionoutlets 31 on the back side of the double striping die 7″ shown in FIG.9 and onto the extruded product 10 or wire 9. The flow channel 29functions to evenly distribute the striping extrusion material to two ormore extrusion chambers 30 for the extrusion of two or moreevenly-distributed stripes onto the extruded product 10 or wire 9.

The striping die adapter 8 may be universally adaptable to variousstriping dies (i.e., single striping die 7′ and double striping die 7″).

It will be appreciated by those skilled in the art that changes could bemade to the embodiments described above without departing from the broadinventive concept thereof. It is understood, therefore, that theinvention disclosed herein is not limited to the particular embodimentsdisclosed, but it is intended to cover modifications within the spiritand scope of the present invention as defined by the appended claims.

What is claimed is:
 1. An apparatus for extruding an outer material ontoan extruded product with one or more longitudinal stripes incorporatedonto the surface of the extruded product comprising: a body having asubstantially tubular shape, an upstream end and a downstream end; aprimary feed conduit extending through the body for conveying a primaryextrusion material; a secondary feed conduit mounted downstream of theprimary feed conduit for conveying a secondary extrusion material; aprimary extrusion head mounted in the body; a secondary extrusion headmounted in the body downstream from the primary extrusion head; a dieretainer mounted to the downstream end of the body; a striping die withan upstream side and a downstream side, wherein the striping die ismounted in the die retainer downstream of said secondary extrusion head;a striping die adapter removably connectable to the downstream side ofsaid striping die; and a striping feed conduit extending through thestriping die adapter for conveying striping extrusion material; whereinthe upstream end of the striping die comprises one or more stripingextrusion outlets for delivering striping extrusion material onto theextruded product; the downstream end of the striping die comprises aflow channel in fluid communication with the one or more stripingextrusion outlets; and the flow channel is wishbone-shaped.
 2. Theapparatus of claim 1 further comprising: a heating element removablyconnectable to the striping die adapter.
 3. The apparatus of claim 1further comprising: a thermocouple port mounted to the striping dieadapter.
 4. An apparatus for extruding an outer material onto anextruded product with one or more longitudinal stripes incorporated ontothe surface of the extruded product comprising: a primary feed conduitsupplying a primary extrusion material through a primary extrusionchamber to coat the extruded product; a secondary feed conduit supplyinga secondary extrusion material through a secondary extrusion chamber tocoat the extruded product; a striping feed conduit supplying a stripingextrusion material onto a striping die, wherein the striping diecomprises an upstream side and a downstream side; and a striping dieadapter for establishing a fluid connection between the striping feedconduit and the striping die; wherein the upstream end of the stripingdie comprises one or more striping extrusion outlets for deliveringstriping extrusion material onto the extruded product; the downstreamend of the striping die comprises a flow channel in fluid communicationwith the one or more striping extrusion outlets; and the flow channel iswishbone-shaped.
 5. The apparatus of claim 4 further comprising: aheating element removably connectable to the striping die adapter. 6.The apparatus of claim 4 further comprising: a thermocouple port mountedto the striping die adapter.
 7. An apparatus for extruding one or morestripes onto an extruded product comprising: a striping die with anupstream side and a downstream side, wherein the upstream side of thestriping die is removably connectable to an apparatus for extruding anouter jacket or insulative material onto the extruded product; and astriping die adapter with an upstream side and a downstream side,wherein the upstream side of the striping die adapter is removablyconnectable to the downstream side of the striping die; wherein thestriping die comprises one or more striping extrusion outlets fordelivering striping extrusion material onto the extruded product; thestriping die comprises a flow channel in fluid communication with theone or more striping extrusion outlets; and the flow channel iswishbone-shaped.
 8. The apparatus of claim 7 further comprising: aheating element removably connectable to the striping die adapter. 9.The apparatus of claim 7 further comprising: a thermocouple port mountedto the striping die adapter.
 10. An apparatus for extruding one or morestripes onto an extruded product comprising: a striping die, wherein thestriping die is removably connectable to an apparatus for extruding anouter jacket or insulative material onto the extruded product; and astriping die adapter removably connectable to the striping die; whereinthe striping die comprises one or more striping extrusion outlets fordelivering striping extrusion material onto the extruded product; thestriping die comprises a flow channel in fluid communication with theone or more striping extrusion outlets; and the flow channel iswishbone-shaped.
 11. The apparatus of claim 10 further comprising: aheating element removably connectable to the striping die adapter. 12.The apparatus of claim 10 further comprising: a thermocouple portmounted to the striping die adapter.